Hole-stitching machine



I APPLICATION FILED MAR-8,1918. v 1,376,658. A

H. UNGER. HOLE STITCHING MAEHINE.

Patented May 3, 1921.

I I i Mlmmnm I l H. UNGER.

HOLE STITCHING MACHINE. APPLICATION FILED MARI B, I9I8. ,1 37 5 Patented May 3, 1921.

4 SHEETS-SHEET 2.

H. UNGER. HOLE STITCHING MACHINE. APPLICATION FILED'MAR. 8 1918.

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Patented May 3,1921.

H. UNGER. HOLE STITCHING MACHINE.

APPLICATION FILED MAR. 8. 191a.

Patented May 3, 1921.

4 SHEETS-SHEET 4.

fabric when the feeder is inits upper po UNITED STATES PATENT OFFICE.

HUGO UNGER, 0F BERLIN, GERMANY, ASSIGNOR TO THE FIRM 0F LINTZ '80 EUR- HAIRDT, OF BERLIN, GERMANY.

HOLE-STITCHING MACHINE.

Application filed March .8, 1918.

To all whom it may concern Be it known that I, HUGO UNGER a subect of the King of Saxony and the erman mperor, residing at 8 Wilhelm Stolzestrasse, Berlin, Germany, have invented certain new and useful Improvements in Hole- Stitching Machines, of which the following is a specification.

When stitching holes with the crank operated stitching machines hitherto known it is necessary to use a rotatable needle plate, provided with a mandrel or finger pro ecting into the hole to be stitched, 1n order to guide the fabric, which fabric 1 s drawn over said finger. For ordinary sewing work this fingered plate must be removed or re placed by a plain needle plate.

According to my invention the replacement of said fingered plate by a plain one is avoided by using as finger the piercer known in hemstitohing crank operated machines, which finger is in such case introduced into a larger opening of the needle plate for doing hole-stitching work. On my improved machine ordinary seams can be made immediately after the stitching of a round hole has been terminated by locking the movement of said piercer and by lifting the same; the ordinary seam can in such case be executed as a zig-zag festoonstitch or as an ordinary double backstitchseam if the mechanism for swinging the needle-bar to and fro is locked at the same time, so that this needle-bar only moves up and down. 7

While stitching the round hole, the mech-- anism for moving the feeder is looked, as is generally known, so that when turning the crank only the barrel with the piercer serving as mandrel and the swinging needle are rotated, whereas the feed-movement of the fabric by the feeder is eliminated. Provision can also be made whereby the piercer is lifted simultaneously with the needle and the feeder moves upward when the needle has gone down. In this case the mechanism for moving the feederup and down needs not to be looked, as the latter holds-the fabric when the needle and the piercer are in their upper position, whereas on the other hand the piercer prevents a movement of the tion.

When the round hole is stitched the mechanism for actuating the piercer is locked in Specification of Letters Patent.

Patented May 3, 1921.

Serial No. 221,271.

such a manner that the piercer is in its upper position and leaves the fabric free to be moved by the feeder. At this stage the mechanism for moving the feeder again comes into activity.

For locking the mechanism moving the feeder during the stitching of the round hole I preferably use an arm rotatable in a known manner on the hand-crank, as is customary in hemstitching machines. A

In the accompanying drawings I have illustrated a hole-stitching machine according to my invention. In these drawings Figure 1 1s a side elevation of the machine from one side and Fig. 2 a similar elevation from the opposite side; Fig. 3 is a front view of the machine; Fig. 4 shows to a larger scale the driving lever for the feeder and F g. 4? another part of the driving .mecha-- IllSIIl. Figs. 5 and 6 are views to a larger scale, showing the locking pawls for holding the feeder and the mechanism for swinging the needle out of activity, and Fig. 7 shows a sample of the stitching made on the machine according to my invention.

The piercer a (Fig. 1) is attached in a known manner to a vertically slidable sleeve a which is connected to a rearwardly extending slide (1 as shown in Fig. 2. To the upper end of this slide is connected an arm a pivotally mounted on abolt a and provided with a movable lug a. This lug is engaged by the horizontal arm of a bell crank lever a which is also pivotally mount ed on the bolt a and which is moved to and fro by a cam a fixed on the main shaft g, whereby the piercer is reciprocated. s

The slide a is provided with-a projection a which in the uppermost position of the slide can beengaged from below by a pawl or stop arm 6 pivotally mounted on avertical bolt. This stop arm is actuated by a horizontal rod 6 which is attached to the arm e fixed on the vertical pivotally arranged shaft 6, so that on turning the latter, said stop 6 can be slid under the proa as stated above. In its normal position the stop 6 engages said projection a and thus retains the piercer in its uppermost position. But when the lever e is slightly turned by a finger of the operator, the stop 6 disengages the projection a so that now the piercer a enters through the fabric to be stitched into the needle plate. When the lever e is released thevertical shaft 6 is turned back in a known manner into the locking position by means of coil-springs arranged thereon.

The feeder b is mounted in a known manner on an arm 6 as shown in Fig. 3. This arm is rocked to and fro by means of swinging arms I), which on their part are actuated by the upand down-movement of a conical socket b operated by a parallel slide 6 the lower end of which is actuated upward by a spring I).

The feeder is driven by a double armed lever 72 which, as shown in Fig. 4, is rotatably mounted on a pivot b and is provided on one arm with a roller 6 actuated by a cam I), mounted on the main shaft g. The arm 6' pointing away from the cam rests on a nose or lug b of the slide 6. The arm of the lever 12'' directed toward the cam I) and bearing the roller 6 is provided with a nose b which can be engaged from below by a pawl or stop 0 rotatably mounted on a pivot 0 as shown in Figs. 1 and 5. A spring 0 tends to remove the stop 0 from the nose 5 of the lever b and at the same time urges the lower arm of the stop 0 which is provided with a roller 0 against its actuating cam f fixed on the shaft f. This shaft carries a tooth-wheel 7 which is in engagement with a smaller tooth wheel on the main shaft g; corresponding to the transmitting ratio of 2 to 1 between the main shaft 9 and I the shaft f, the stop 0 is also moved to and fro in the same relation to the upand down-movement of the needle-bar, so that the lever?) actuating the feeder is free during one stitch and retained in its lower position during the next stitch.

7 On the pivot a carrying the stop a is a second stop h which, as shown in Figs. 1 and 5, is rotatably mounted and the horizontal arm of which may be brought into engagement with a bell-crank lever 2' by means of a spring h. This bell-crank lever'z' is rotatably mounted on a pivoti and carries on the upper end of its'vertical arm a roller i engaging a cam f fixed on the shaft f.- In the horizontal arm of the bell-crank lever i a hook i is provided for a screw i supporting a lever i which can turn loosely on the pivot 7' as shown in Fig. 6 representing a section on the line wm in Fig. 5. When the vertical. arm of bell-crank lever c is pushed to the right by cam f acting on roller 77, the screw 11 bearing against the lower face of lever 2' draws this lever with it and thus lifts a pin 15 of the slide i actuated downwardly by the spring 71 which pin rests on the end of lever i The slide 2' is connected with the collar 2' which actuates the needle-bar in a known manner by means of an oblique slot, so that when the needle vibrating'the collar 2' moves up and down the needle-bar is swung back and forward pricking the fabric in a zigzag fashion.

When the vertical arm of the bell-cranklever dis in its right position, as shown in Fig. 5, the stop it, influenced by a spring 71., can snap in front of the lever 1', whereby the lateral motion of the needle-bar is interrupted. The spring 71 tends to press the slide 2' with the collar 71 downward whereby the slide 'z" takes with it the lever 2' loosely pivoting on i by means of the pin i This movement of. the slide i is limited by a set-screw 2' engaging the lower face of lever i as shown in Fig. 1 whereby the vibration stroke of the needle can be regulated according to the thickness of the piercer. For a thicker piercer the screw 2' must be screwed higher. By means of the screw 2' the stroke of the needle is regulated toward the outside, a. away from the piercer; therefore the oscillations or vibrations ofthe needle can be varied by the screw i.

When these oscillations or vibrations are properly adjusted the lever 71 is fastened to the lever i pivoting on pivot i by means of a screw i which passes through a slot of the lever i and for which the horizontal short arm of lever 71 serves as a nut, as shown in Fig. 5.

. Both of the stops 0 and k may be turned on their pivot 0 so that the stop 0 arrests the feeder actuating lever 5, thereby interrupting the feeding motion of the feeder, 105 and the horizontal arm of the stop it releases the lever i so that it can be set into motion by the cam i and vibrates the needle bar to and fro. This turning of, the stops is offected by means of a slide rod 6 one .end of 110 which is'adapted to engagethe vertical arms of the stops, when said rod is pushed for ward by an arm e mounted on the upper end of the vertical shaft 0 p H The arms 6 and'e of the vertical shaft e 115 point into opposite directions, so that when the rod 6 is pushed forward, rod 6 is simultaneously withdrawn and vice versa.

The described mechanism acts in the following manner.

When the lever e ofcrank d remains unin fiuenced, the rods e and e occupy the positions shown in Fig. 1. The piercer a is retained in its upper position, because the i stop 6 pushed forward by rod 6 pro 125 jects under the nose a? of the piercereslide a as shown in Fig. 2. Furthermore the horizontalarm of the stop it lies in front of the not locked and is therefore moved backand forward by the cam f", on the countershaft driven from the shaft 9 so that the feeder comes into action, according to the transmitting-relation between the shafts g and 7. An ordinary straight seam as shown for instance at m in Fig. 7 is then produced. If at the same time the stop '71., shown in Fig. 5, were moved to the left, by means of any mechanism, and retained in this position for instance by a set screw not shown in the drawing, the collar 2' would be moved up and down by the lever 11 to vibrate the needle, so that a zigzag-shaped seam would be produced.

But ifthe lever e is shifted and thereby the vertical shaft e is so turned that rod e is pushed forward and rod 6 withdrawn, then on the one part the stops 0 and h are thrown over, so that the forwarding motion of the feeder is interrupted and the swing ing motion of the needle-bar becomes possible, whereas on the other part the stop c is withdrawn, so that the piercer is released and can prick into the fabric. A round hole 11. as shown in Fig. 7 is then stitched by causing the crank to perform a circular movement.

During this operation the feeder remains idle, so that the fabric is atrest. On releasing the lever e the sewing work can be directly continued.

I claim 1. In an eyelet stitching machine, a needle bar, mechanism vibrating it, separate mechanism'for reciprocating the needle bar, a fabric feeder, a piercer and mechanism for operating the piercer, in. combination with mechanism to lock the feeder and simultaneously release the needle bar vibrating mechanism and the piercer operating mechanism and vice versa, whereby a continuous seam may be produced immediately after the formation of an eyelet and vice versa.

2. In a crank-operated eyelet stitching machine, a stop mechanism, a stitch forming mechanism including needle vibrating and needle reciprocating mechanisms, a piercer and piercer operating mechanism, a fabric feeder and feeder operating mechanism, and a crank for controlling the circular stitching, and means actuated at the crank by the stitcher to operate said stop mechanism to simultaneously arrest the needle vibrating and piercer actuating mechanism and simultaneously release the feeder operating mechanism and vice versa.

In testimony whereof I have signed my name to this specification, in the presence of two subscribing witnesses.

HUGO UNGER.

Witnesses GERTRUD KRUOZKOWSKI, MARGARETHTE WEGNER. 

